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<head><title>what is a subquotient module?</title>
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<div><h1>what is a subquotient module?</h1>
<div>There are two basic types of modules over a ring R: submodules of R^n and quotients of R^n. Macaulay2's notion of a module includes both of these. Macaulay2 represents every module as a quotient image(f)/image(g), where f and g are both homomorphisms from free modules to F: f : F --> G and g : H --> G. The columns of f represent the generators of <tt>M</tt>, and the columns of g represent the relations of the module M.<table class="examples"><tr><td><pre>i1 : R = ZZ/32003[a,b,c,d,e];</pre>
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Include here: generators, relations.</div>
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